ARI: Add ability to raise arbitrary User Events

User events can now be generated from ARI.  Events can be signalled with
arbitrary json variables, and include one or more of channel, bridge, or
endpoint snapshots.  An application must be specified which will receive
the event message (other applications can subscribe to it).  The message
will also be delivered via AMI provided a channel is attached.  Dialplan
generated user event messages are still transmitted via the channel, and
will only be received by a stasis application they are attached to or if
the channel is subscribed to.

This change also introduces the multi object blob mechanism used to send
multiple snapshot types in a single message.  The dialplan app UserEvent
was also changed to use multi object blob, and a new stasis message type
created to handle them.

ASTERISK-22697 #close
Review: https://reviewboard.asterisk.org/r/3494/
........

Merged revisions 414405 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@414406 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 84 insertions, 0 deletions

diff --git a/res/res_stasis.c b/res/res_stasis.c
index d9542cd21..0184d209c 100644
--- a/res/res_stasis.c
+++ b/res/res_stasis.c
@@ -61,6 +61,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/stasis_app_impl.h"
 #include "asterisk/stasis_channels.h"
 #include "asterisk/stasis_bridges.h"
+#include "asterisk/stasis_endpoints.h"
 #include "asterisk/stasis_message_router.h"
 #include "asterisk/strings.h"
 #include "stasis/app.h"
@@ -1310,6 +1311,89 @@ enum stasis_app_subscribe_res stasis_app_unsubscribe(const char *app_name,
 		json, app_unsubscribe);
 }
 
+enum stasis_app_user_event_res stasis_app_user_event(const char *app_name,
+	const char *event_name,
+	const char **source_uris, int sources_count,
+	struct ast_json *json_variables)
+{
+	RAII_VAR(struct stasis_app *, app, find_app_by_name(app_name), ao2_cleanup);
+	RAII_VAR(struct ast_json *, blob, NULL, ast_json_unref);
+	RAII_VAR(struct ast_multi_object_blob *, multi, NULL, ao2_cleanup);
+	RAII_VAR(void *, obj, NULL, ao2_cleanup);
+	RAII_VAR(struct stasis_message *, message, NULL, ao2_cleanup);
+	enum stasis_app_subscribe_res res = STASIS_APP_USER_INTERNAL_ERROR;
+	struct ast_json *json_value;
+	int have_channel = 0;
+	int i;
+
+	if (!app) {
+		ast_log(LOG_WARNING, "App %s not found\n", app_name);
+		return STASIS_APP_USER_APP_NOT_FOUND;
+	}
+
+	blob = json_variables;
+	if (!blob) {
+		blob = ast_json_pack("{}");
+	}
+	json_value = ast_json_string_create(event_name);
+	if (!json_value) {
+		ast_log(LOG_ERROR, "unable to create json string\n");
+		return res;
+	}
+	if (ast_json_object_set(blob, "eventname", json_value)) {
+		ast_log(LOG_ERROR, "unable to set eventname to blob\n");
+		return res;
+	}
+
+	multi = ast_multi_object_blob_create(blob);
+
+	for (i = 0; i < sources_count; ++i) {
+		const char *uri = source_uris[i];
+		void *snapshot=NULL;
+		enum stasis_user_multi_object_snapshot_type type;
+
+		if (ast_begins_with(uri, "channel:")) {
+			type = STASIS_UMOS_CHANNEL;
+			snapshot = ast_channel_snapshot_get_latest(uri + 8);
+			have_channel = 1;
+		} else if (ast_begins_with(uri, "bridge:")) {
+			type = STASIS_UMOS_BRIDGE;
+			snapshot = ast_bridge_snapshot_get_latest(uri + 7);
+		} else if (ast_begins_with(uri, "endpoint:")) {
+			type = STASIS_UMOS_ENDPOINT;
+			snapshot = ast_endpoint_latest_snapshot(uri + 9, NULL);
+		} else {
+			ast_log(LOG_WARNING, "Invalid scheme: %s\n", uri);
+			return STASIS_APP_USER_EVENT_SOURCE_BAD_SCHEME;
+		}
+		if (!snapshot) {
+			ast_log(LOG_ERROR, "Unable to get snapshot for %s\n", uri);
+			return STASIS_APP_USER_EVENT_SOURCE_NOT_FOUND;
+		}
+		ast_multi_object_blob_add(multi, type, snapshot);
+	}
+
+	message = stasis_message_create(ast_multi_user_event_type(), multi);
+	if (!message) {
+		ast_log(LOG_ERROR, "Unable to create stasis user event message\n");
+		return res;
+	}
+
+	/*
+	 * Publishing to two different topics is normally to be avoided -- except
+	 * in this case both are final destinations with no forwards (only listeners).
+	 * The message has to be delivered to the application topic for ARI, but a
+	 * copy is also delivered directly to the manager for AMI if there is a channel.
+	 */
+	stasis_publish(ast_app_get_topic(app), message);
+
+	if (have_channel) {
+		stasis_publish(ast_manager_get_topic(), message);
+	}
+
+	return STASIS_APP_USER_OK;
+}
+
 void stasis_app_ref(void)
 {
 	ast_module_ref(ast_module_info->self);